This is a competitive renewal application to participate in the Cooperative Neonatal Research Network. The Brown University Program of the Network will be completing its fourth year of participation on the Network and would like to continue the involvement in the next five years cycle. Our Department of Pediatrics and its Division of Neonatal Perinatal Medicine has a strong commitment to this Project and will continue to use Women and Infants Hospital (WIH) as the performance site. WIH is the only Perinatal Tertiary Care Center for the State of RI and Southeastern Massachusetts; it has a 60-bed Neonatal Intensive Care Unit and had a birth rate of 9,500, a high risk maternal transfer rate of 812, and a neonatal transfer rate of 185 in 1994. The hospital is also the primary affiliated institution for the teaching of Obstetrics and Gynecology and Neonatology for Brown University School of Medicine. The Department of Obstetrics and Gynecology has 17 full time faculty with 6 in the Division of Maternal Fetal Medicine. The Department of Pediatrics has 70 full time faculty with 12 in the Division of Neonatal Perinatal Medicine who are based at WIH. Seven of the 12 Division Faculty members are in the academic track and are all involved in research. The Division is also funded by several external granting agencies including NIH. With the abundance of patient resource, our commitment to research, and the availability of a multitude of research talents in our group, we believe that the Brown program can contribute significantly to the Network in performing collaborative clinical investigations in the forthcoming years.